what type of cooling system do I have ??

[boardmonkey]

Hi,

I have a late model thermostat fitted but without a coolant distribution pipe as indicated in this picture.

I am replacing thermostat housing and top, when I removed the top of this housing the water was typical rad colour, brown..

I then removed the sensor, the water that came out was almost clear with a slight bluish tinge..!
I cannot understand why this would be or why I have no coolant distribution pipe, are the 2 connected..

Thanks, Richard

[kevtherev]

The coolant distributor is not immediately visible..are you sure?
Yes the thermostat housing and distributor are connected, they have to be during warm up, as the coolant circulates around the engine bypassing the thermostat until it gets warm enough to open..then the thermostat closes the bypass

[boardmonkey]

Hi Kev,

Yeah right its not visible, found it with my fingers - behind the engine bay bulkhead completely hidden from view.


Any thoughts on the different colour of coolants ? I know the thermostat is working as thats been tested and opens & closes...

[dumbo]

brown coolant sounds like rust???? or head gasket???

[dumbo]

brown coolant sounds like rust???? or head gasket???

[boardmonkey]

Hi,

Yes, that maybe the case, i did replace the head gaskets a few years back, plus new studs - im going to flush the system anyway..but rather confused as to why the difference in colour....

[kevtherev]

Hi,



I am replacing thermostat housing and top, when I removed the top of this housing the water was typical rad colour, brown..

I then removed the sensor, the water that came out was almost clear with a slight bluish tinge..!
I cannot understand why this would be or why I have no coolant distribution pipe, are the 2 connected..

Thanks, Richard

I believe it should be pink as G12 is pink.
G12 is primarily a rust inhibitor and secondly an anti freeze, which is why VW recommends it for the WBX eng.

As to why you have differing liquids, that needs further investigation. And more clarification from you.
But I will hazzard a guess.
Radiator cores do not rust, the rusty coolant is from the iron barrels and head bolts. the difference can be from a cooling system not circulating, after a coolant change.

We can assume you thermostat is the right way up?
..and it opens at 87 deg C

[Ralf85]

Update. If you get the antifreeze from a VW garage the latest version is G13, but G12 or G12+ are the earlier versions.

[kevtherev]

Update. If you get the antifreeze from a VW garage the latest version is G13, but G12 or G12+ are the earlier versions.

It's still pink

[lloydy]

Nope, purple

All backward compatible though

[kevtherev]

Nope, purple

hair splitter!

[boardmonkey]

As to why you have differing liquids, that needs further investigation. And more clarification from you.
But I will hazzard a guess.
Radiator cores do not rust, the rusty coolant is from the iron barrels and head bolts. the difference can be from a cooling system not circulating, after a coolant change.

We can assume you thermostat is the right way up?
..and it opens at 87 deg C

Hi Kev, Yes Id say it was the right way round, although its out of the thermostat now as Ive taken it out and tested it by adding it to a saucepan of hot water that I heated and it opened, I took it out and as it cooled it closed again.

Would it fit both ways ? I mean its been in the van like that for 3-4 years and the vans been MOTd and driven from London to Cornwall...

[kevtherev]

Looks like this?
the valve on the bottom closes as the top opens

[boardmonkey]

Hi Kev,

Thanks - I checked the thermostat this morning, it will only fit in one way.
So when you test these, should you see both valves opening ? I didnt check the secondary one....although I notice they both open and close as one, rather than independently of each other...

Im going to flush the system and refill, bleed as parts have arrived today..

Heres mine, it is stamped 87 deg.